Engine starter



Nav. 29, 1927.

W. L. McGRATH ENGINE STARTER Filed NOV. 5, 1923 I, 2 Sheets-Sheet lNORM/7L 0f? DEMESHED P05/770/V my. 29, :1x y, mm@

w. L. MGGRATH ENGINE STARTER yFiled Nov. 5, 1923 2 Sheets-Sheet 2Patented Nov.. 29, 1927.

STATE@ FFMCE.

WILLIAM'L. MCGRATH, OF ELMIRA, NEW YORK, ASSIGNOR T0 ECLIPSE MACHINECOMPANY, OF ELMIRA, NEW YORK, A CORPORATION OF,NEW YORK.

ENGINE STARTER.

`Application filed November 5, 1923. Serial No. 672,911.

My invention has relation to means for starting or cranking an enginesuch as an internal combustion engine, and more particularly to thatpart of the enginestarter system known as the drive or transmissionwhich transmits the power of the prime mover such as an electric motorto a member of the engine to be started such as the flywheelthereofpsuch drive being capable of manual operation for engagement withthe engine member and of automatic disengagement therefrom when theengine oper-A ates under its own power. In the practice of my invention,a driving member such as a pinion which is adapted to engage or meshwith the engine member cooperates with a spring adapted to hold suchpinion in a normal position upon its shaft, and the objectof myinvention is to provide means whereby the pressure or tension of thisspring may be varied according to the different relative positions ofthe pinion on its shaft, in particular to lessen the tension of thespring at the time of the disengagement of the pinion from the enginemember' or fly-wheel when there should be substan` tially no resistanceencountered by the pinion in its longitudinal movement for that purpose.

In the drawings,'Figure l is a sectional elevation of the engine startersystem embodying my invention and showing the parts in their normal ordisengaged position;

Fig. 2 a View similar to Fig. l but showing' the parts in engagedposition; Fig. 3 a section on the line 3 3 of Fig. 1; Fig. 4 a viewsimilar'to Fig. l but showing the inboard type ,of installationA andwith the parts in disengaged position; and Fig. 5 a view similarv toFig. 4 but illustrating the engaged position of the parts.

Referring to the embodiment of my invention as herein shown. the startermotor l is provided with an extended armature Y f shaft 2 having asuitable bearing 3 at its o'uier end. Upon this driving or armatureshaft a hollow shaft or sleeve 4 is mounted for longitudinal movementthereof and for rotinv movement therewith, through suitable means suchas the longitudinal splines 5 engaged by the bore of the hollow shaft orsleeve. This shaft is provided with a screw threaded portion 6 and may,therefore, be termed a screw shaft. As a sepadifferent rate or integralpart thereof, the screw shaft is provided at itsinner end with parallelflanges 7 forming a circumferential groove 8 with which cooperates theroller 9 oni the shifting means. Such shifting means may be of anysuitable character and as shown the same consists of a lever 10 pivotedat 1l and actuated by the'operator by either foot or hand.

Upon the screw threaded ortion of the screw shaft orsleeve is threa edthe/,driving member which is in the form of a pinion 12 adapted to meshwith the engine member or flywheel 13. This pinion is, therefore,mounted upon/the screw vshaft for rotary movement therewith and forlongitudinal movement thereof. It is normally held against the stop nut14. secured to the outer end of the screw shaft, the same beingyieldingly held thereagainst in this normal position in a, yieldingmanner by means of a coil spring 15. This spring encircles the screwshaft and operates against the inner face of the the spring cup orretainer 16. The object of the present invention is to provide meanswhereby the tension of this spring against the pinion -may be variedaccording to the phases in the cycle of operation of the drive.

To this end, means are provided for shifting the abutment of the innerend 0f the spring towards and away from the pinion with the result thata maximum or minimum degree of tension or pressure may be exerted by thespring upon the pinion. Specifically such means comprise alongitudinally movable abutment for the inner end of the spring whichabutment is controlled according to the di'erent phases of operation bya system of levers under the control of the 4relative position of thescrew shaft upon the armature shaft.

As herein shown, the inner endof the `spring cooperates with alongitudinally movable abutment iwhich is in the form of a ring U-shapedin cross section as illustrated in Fig. 1. This ring is adapted to slidelonpinion either directly or through gitudinally upon a collar formed intwo sections 18, 18 which is secured to the screw shaft in a suitablemanner as by means of the screw or dow'el pin 19. Betweenthe twosections 18 ,of this collar, there is interposed and held by the dowelpin 2O a washer 21 y ginnin shown in Fig.

having an upwardly extending bracket portion 22 bent outwardly at 23 andprovided at its extreme outer end with a pivot pin 24. Upon this pin ispivoted a yoke 25 whose arms are pivoted at 2G to opposite sides of thespring abutment 17. The yoke 25 is actuated by means of a lever or bellcrank 27 which is pivoted to the collar 18 on the pivot pin 28 extendingacross the longitudinal slot 29 in the screw shaft. The elbow of thisbell crank is normally positioned upon the periphery 30 of the armatureshaft, but when the screw shaft is shifted outwardly longitudinally ofthe armature shaft, such elbow will ride down upon the slope 31 and uponthe reduced portion of the armature shaft between its splines with theresult that the upper or free end of the bell crank will be withdrawnfrom its contact with the yoke 25 and thereby permit such yoke andconsequently the spring abutment 17 to move inwardly from the positionshown in Fig. 1 to the position shown'in Fig. 2. Thereupon, the spring15 which was under some compression when in the normal position shown inFig. 1 now exerts a minimum or practically no pressure at all againstthe pinion as shown in Fig. 2.

The pinion is held in a retracted position on the screw shaft by meanswhich form no part of the present invention, but nevertheless will bedescribed as follows: A latch 32 is pivoted upon the pin 28 and has arearward portion which normally rests upon the shaft periphery 30, butwhich when the screw shaft is shifted outwardly rides down the slope 31and thereby permits the outer end of the latch to project upwardlythrough the slot 29 in position to engage a notch in the bore of thepinion thereby preventing the same from rotating and from being returnedb spiral movement to its normal position at t e outer end of the screwshaft. The latch 32 is spring pressed in one direction by the spring 33.

Describin a cycle of operation and bewit i the parts in their normalposition s iown in Fig. 1, the operator actuates the shifting means 10and thereb shifts the drive assembly outwardly to t e position 2. Inthis shifting operation, the pinion 12 engages the fzywheel 13 and atthe same time the bell crank 27, being no longer supported by thearmature shaft, will permit the tension of the spring 15 to thrust theabutment 17 inwardly, the yoke 25 oscillating to the position shown inFig. 2. Consequently, the spring 15 presents a minimum or practically notension whatever against the pinion 12. As an incident to the operationof the shifting means or as a-separate operation, the switch of themotor is ogprated and current is supplied thereto ereupon` the wer ofthe motor will be transmitted to e ywheel and the engine will berotated. The pinion will now be demeslied by overrunning the screwthreads, the pinion moving longitudinally of the shaft and away from thestop nut. When the pinion comes into the range of the latch 32, it willbe caught and retained thereby against return in the other direction. Atthe initiation of this demeshing operation, the tension of the spring isat a minimum and consequently the resistance to demeshing is at aminimum and the catching of the pinion is assured.

After the pinion is demcshed. it will compress the spring in its finallongitudinal movement and will be caught by the latch and held in suchdemesbed position so that such pinion cannot be returned against the nowrotating flywheel even if the screw shaft should remain in its outwardlyshifted position. Upon the final return movement of the screw shaft, theelbow of the bell crank 27 will ride up the slope 31 and upon theperiphery 30 of the armature shaft whereupon the bell crank willoscillate the yoke 25 in an outward `direction and move the springabutment 17 outwardly thereby compressing the spring 15. At the veryfinal movement of the return of the screw shaft, the latch 32 will beactuated and the pinion will thereby be released and the increasedtension o the spring 15 will be utilized to spil-ally move the pinion 12outwardly and thereby return it to its normal position against the stopnut 14.

As will be obvious, the relationship of the inner end of the latch 32and the elbow of the bell crank 27 may be varied so that their movementcaused by the contacting of the slope 31 may bring about thelongitudinal outward movement of the spring abutment 17 either ybeforeor after the latch releases the pinion, and the interval may be'madc andesired amount.

n Figs. 1, 2 and 3, lnfy invention is shown embodied in a drive o theoutboard type, that is the type'in which the pinion moves outwardly awayfrom the starting motor when meshed with the flywheel and in Figs. 4 and5, I have shown my invention applied to a drive of the inboard type inwhich the inion is moved inwardly towards the startlng motor when meshedwith the flywheel. The construction and mode of operation are the samein both instances and the same figures of reference are applied to thecorresponding parts. However, there is a slight difference over theconstruction shown in Figs. 1, 2 and 3 in that the periphery 30 andslope 31 are not inte ral with the armature shaft but are formedgby aseparate sleeve 34 secured to the armature shaftand having a beveledinner end 35 to provide such slope. This sleeve is secured to thearmature shaft in a novel manner whereb the same may he readilyassembled and isassembled. As

lil

shown in Fig. 5, the armature shaft is provided at its outer'end with aradial hole or cavity 36 in which slides a pin or plunger 37, springlpressed outwardly by means of a spring 38. The head of this plungerwhich is of smaller diameter normally projects through a hole 39 in thesleeve 3dwith the result that such sleeve is secured to the armatureshaft against movement in any direction. The Aplunger may be presesdiiiwardly and out of the hole 39 whereupon the sleeve 3ft may be readilydrawn outward-` l v and removed from its armature shaft, therebyTpermitting the entire assembly to be slid od the shaft. rlhere is thusprovided simple means permitting of ready assembly and disassembly andof positively locking the parts in place, i

l do not herein broadly claim the coiistruction and the arrangement ofthe drive including the longitudinally shiftable sleeve or drivingmember or inion thereon and the. catch device for holding the pinion indemeshed position while the screw shaft or sleeve is still shifted tocranking position as the same represent subject matter of my priorapplications for patent including application tiled on January et,19:23, Serial No. 610,672, the present application being directed to theparticular invention pointed out in the claims herein.

l claim:

1. An engine starter drive including a rotatable shaft, a driving membermounted thereon for rotary movement therewith and for longitudinalmovement thereof, yielding means cooperating with the driving member tohold it to a normal position on the shaft, an abutment therefor, andmeans for shifting the abutment during the operation of the drive todifferent positions to vary the degree of pressure of suoli yieldingmeans.

2. An engine starter drive including a rotatable shaft, a driving membermounted thereon for rotary movement therewith and for longitudinalmovement thereof, a spring cooperating with the driving member, anabutment therefor, and means for shifting the abutmenty during theoperation of the drive todiiferent positions to vary the degree ofpressure of suoli yielding means.

2l. An engine starter drive including a rotatable shaft, .a drivingmember mounted thereon for rotary movement therewith and forlongitudinal. movement thereof, said shaft being longitudinally movable,yielding means cooperating with the driving member to hold it to anormal position on the shaft, an abutment therefor, and means under thecontrol of the longitudinal movement of the .shaft for shifting theabutment to different positions to vary the 'degree of pressure of lsuchyielding means.

4. An engine starter drive including a rotatable shaft, a driving membermounted driving mem thereon for'rotary movement therewith arid forlongitudinal movement thereof, a spring acting on the driving membertending to hold it to a normal position on the shaft, and means forshift-ing the spring to ditleient positions according to the positionlofthe driving member relative to the shaft.

y 5. An engine starter drive including a 1'otatable shaft, a driving'member mounted thereon for rotary movement therewith and forlongitudinal movement thereof, a spring yacting on the driving membertending to hold it to a normal position on thesliaft, an abutmenttherefor, and means acting on the abutment for bodily shiftingit todifferent positions to vary the degree of pressure of the spring. I i

6. An engine starter drive including a rotatable shaft, a driving membermounted thereon for rotary movement therewith and for longitudinalmovement thereof, a spring acting on the driving member tending to phold it to a normal position on the shaft, au

abutment which slides u on the shaft and against which one end 'o' thespring bears,

and means for sliding the abutment to vary the degree of pressure of thespring.

7. An engine starter drive including a longitudinally movable rotatableshaft, a

driving member mounted thereon for rotary movement therewith and forlongitudinal' vil() movement thereof, a spring acting on the drivingmember tending to hold it to a noi"- mal position on the shaft, anabutmentl against which one end of the sprin bears, and means controlledby the longitudinal Yioo movements of the shaft for shiftingsaidabutment to different positions.

8. An engine starter drive including a` movable rotatable shaft, a

longitudinall lier mounted thereon for rotary driving mem movementtherewith and for longitudinal movement thereof, a spring acting on thedriving member tending to hold it to a noi'- mal position on the shaft,and means controlled by the longitudinal movements of the `shaft forshifting the spring to different positions.

9. An engine starter drive including aV movable rotatable shaft, f a rmounted thereon for rotary movement therewith and for longitudinalmovement thereof, a sprin actingon 4the driving member tending to lgioldit toa noi'- mal position on the shaft, and mea-ns controlled by thelongitudinal movements of the shaft for shifting the spring toldifferent positions, said means comprising an4 abutment and leverscooperating therewith for moving such abutment lon itudinally'.

10. An engine starter( riveincltiding .a longitudinall movablerotatablel shaft, a driving mem er mounted thereon for rotary movementtherewith and for longitudinal movement thereof, a spring acting on thelongitudinally lll) vlill) driving member tending to hold it to a normalposition on the shaft, and means controlled by the longitudinalmovements of the shaft for shifting the spring to different positions,said means comprising a spring abutment in the form of a ring mounted toslide' longitudinally on the shaft, a pivoted yoke pivotally connectedwith the rin and a. lever which is mounted on the shaft and moved inaccordance with the longitudinal movements of the shaft, said lever inits movements controlling the movements of the yoke and consequently theposition of the ring.

11.` An engine starter drive including a longitudinall movable rotatableshaft, a driving mem r mounted thereon for rotary movement therewith andfor longitudinal movement thereof, a spring acting on the driving membertending to hold it to a normal position on the shaft, and meanscontrolled by the longitudinal movements of the shaft for shifting thespring to different positions, said means comprising a spring abutmentmounted to slide longitudinally on the shaft, a bracket connected to theshaft, a yoke pivoted to the bracket and to the abutment, and a leverwhich 'is plvoted on the shaft and moved in accordance with thelongitudinal movements of the shaft, said lever in its movementscontrolling the position of the yoke and consequently of the abutment.

12. An engine starter drive including a longitudinally movable rotatableshaft, a driving member mounted thereon for rotary movement therewithand for longitudinal movement thereof, a sprin acting on the shaft, andmeans controllec by the longitudinal movements of the shaft for shiftingthe spring to different positions with respect to the driving member,said means comprising a sleeve secured to one end of the shaft, anabutment a ainst which one end of the spring bears an which slideslongitudinally on the sleeve, a yoke pivoted upon the sleeve and pivotedto the rlng, and a lever which is pivoted on the shaft and moved inaccordance with the longitudinal movements of the shaft, said lever inits movements controlling the position of the yoke and consequently lofthe abutment.

13. An engine starter drive including a rotatable shaft, a drivingmember mounted thereon for rotary movement therewith and forlongitudinal movement thereof, a spring actin on the driving membertending to hold 1t to a normal position on the shaft, a driving shaft onwhich the rotatable shaft is mounted for longitudinal movement thereofand rotary movement therewith, said driving shaft having a slopingannular shoulder towards one end, said rotatable shaft having alongitudinal slot adjacent said shoulder, and means for shifting thespring to different positions with respect to the driving member, suchmeans comprising an abutment in the form of a ring against which one endof the spring bears and which is adapted to move longitudinally withrespect to the rotatable shaft, a pivoted yoke pivotally connected tothe ring, and a lever pivoted in said slot and controlled in itsmovements by said shoulder and cooperating with the yoke andconsequently the ring to shift them to different positions.

14. An engine starter drive including a rotatable shaft, a drivingmember mounted thereon for rotary movement therewith and -forlongitudinal movement thereof, means for holding the driving member in aretracted position on the shaft, yielding means cooperating with thedriving member tending to hold it in a normal position on the shaft, anabutment therefor, and means for shifting the abutment to differentpositions to vary the degree of pressure of such yielding means.

15. An engine starter drive including a driving shaft, a hollow shaftmounted thereon for longitudinal movement thereon and rotary movementtherewith, a driving member mounted on the hollow shaft for rotarymovement therewith and for longitudinal movement thereof into engagementwith a member of the engine to be started and a sleeve fitting upon oneend of the driving shaft and having a pin and hole connection with thedriving shaft.

16. An engine starter drive includinga driving shaft, a hollow shaftmounted tlercon for longitudinal movem'ent thereon and rotary movementtherewith, av driving mem ber mounted on the hollow shaft for rotarymovement therewith and for longitudinal movement thereof into engagementwith a member of the engine to be started, a sleeve fitting upon one endof the driving shaft, and a spring pressed pin in the driving shaft,said driving shaft having a hole through which such pin normallyextends.

17. An engine starter drive including a rotatable shaft, a drivingmember mounted thereon for rotary movement therewith and forlongitudinal movement thereof, yieldin 1 means acting on the drivingmember temi ing to hold it to a normal position on the shaft, and meansacting during the operation of the drive whereby the degree of pressureof such yielding means is varied.

18. An engine starter drive including a rotatable and longitudinallymovable shaft, a driving member mounted thereon for rotary movementtherewith and for longitudi nal movement thereof, yielding means actingon the driving member tending to hold it toward one end of the shaft,and means acting during vthe operation of the drive for varying thepressure of such yielding means upon the driving member.

lll)

notogese the operation of the drive whereby the de-` gree of pressure ofsuch yielding means is` means acting on the driving member tend` ingtohold it to a normal position on the shaft, and means whereby thedegree of pressure of such ielding means is varied according to thei'erent positions of the movable parts in the operation of the drive.

2.9.-. ln engine starter drive including -a rotatable shaft, a drivingmember mounted thereon for rotary movement therewith and' forlongitudinal movement thereof, meansfor holding the driving member in aretracted posltion on the shaft, yielding means acting on the drivingmember tending to hold it to a normal position on the shaft,

andmeans whereby the degree of pressure of such yielding means isvaried.

23. An engine starter drive including a rotatable shaft, a drivingmember mounted thereon for rotary `movement therewith and forlongitudinal movement thereof, a catch device mounted on the shaft in`position to engage thedriving member and hold it in a retracted positionon the shaft, a spring acting 0n the driving member tending 'to hold itto a normal position on the shaft, and means whereby the degree ofpressure stage of operation of the parts.

' 24. An en ine starter drive including a rotatable shatt, a drivingmember mounted thereon for rotary movement therewith and forlongitudinal movement thereof, yielding means cooperating with thedriving member to hold it to a normalposition on the shaft, an abutmenttherefor, and means responsive to the operation of the drive forshifting the abutment to different positions to vary the degree ofpressure of such yielding means. y

- 25. An engine starter drive including a rotatable screw shaft, apinion threaded thereon for rotary movement therewith. and forlongitudinal movementthereof, a spring cooperating with the inion tohold it to a normal position on t ye shaft, an abutment therefor andmeans res onsive to the operation of the drive for shifting the abutmentto different positions to varythe degree of pressure of such s ringduring a cycle of operation of the drive i... Meern.

50 of such spring is varied1 according to the

